Anthraquinone derivatives containing an ortho- or para-dihydroxyphenylalkylamino substituent



United States Patent ANTHRAQUINONE DERIVATIVES CONTAINING AN ORTHO- 0R PARA-DIHYDROXYPHENYL- ALKYLAMINO SUBSTITUENT Elkan R. Blout, Belmont, Marilyn R. Cohler, Boston, and Milton Green and Myron 8. Simon, Newton, and Robert B. Woodward, Belmont, Mass., assignors to Polaroid Corporation, Cambridge, Mass., a corporation of Delaware No Drawing. Filed Oct. 25, 1963, Ser. No. 318,827

14 Claims. (Cl. 260-371) The present application is a 'continuation-in-part of application Serial No. 824,786, filed July 3, 1949, (now abandoned) which in turn is a continuation-in-part of application Serial No. 478,922, filed December 30, 1954 (now abandoned).

This invention relates to photography and more particularly to products, compositions and processes for the development of photosensitive silver halide elements.

It is one object of the present invention to provide novel processes and compositions for the development of silver halide emulsions, in which novel 'coloreddeveloping agents are used to develop a latent image.

Another object is .to provide novel processes and compositions for the development of silver halide emulsions, in which the novel developing agent is capable of developing a latent image and imparting a reversed or positive colored image of said latent image to a superposed image-receiving material.

A further object is to provide novel products, processes and compositions suitable for use in preparing monochromatic and multichromatic photographic images.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products and compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

The objects of this invention may be accomplished by the use of certain novel dyes which have the ability to develop latent images present in an exposed silver halide emulsion; thus they may be referred to as dye developers. These novel dyes or dye developers will be further described hereinafter.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of a latent image present in a photosensitive element, such as an exposed silver halide emulsion, whereby a positive dye image thereof may be imparted to another element, herein referred to as an image-carrying or image-receiving element.

US. Patent No. 2,983,606, issued May 9, 1961, to Howard G. Rogers, discloses diffusion transfer reversal processes wherein a photographic negative material, such as a photographic element comprising an exposed silver halide emulsion layer containing a latent image, is developed in the presence of a dye developer to impart to an image-receiving element a reversed or positive dye In carrying out the process of this invention, a photosensitive element containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, on an image-receiving element. In a preferred embodiment, the photosensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the latent image is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developed silver, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently due, at least in part, to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It may also be due, in part, to a tanning effect on the emulsion by the oxidized developing agent. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving element, said transfer substantially excluding silver or oxidized dye developer. The latter element receives a depthwise diffusion, from the emulsion, of unoxidized dye developer, without appreciably disturbing the imagewise distribution thereof, to provide a reversed or positive, colored image of the negative image.

image of said latent image by permeating into said emulsion layer a suitable liquid processing composition and bringing said emulsion layer into superposed relationship with an appropriate image-receiving layer. T he inventive concepts herein set forth provide novel dye developers for use in such processes.

The image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer. Inbibition periods of approximately one minute have been found to give good results, but this contact period may be adjusted where necessary to compensate for variations in temperature or other conditions. The desired positive image is revealed by stripping the image-receiving element from the photosensitive element at the end of the imbibition period.

The dye developers of this invention may be utilized in the photosensitive element, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving element when in superposed relationship therewith. Placing the dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any lightfiltering action by the colored dye developer. In this pre ferred embodiment, the layer of dye developer may be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Similar concentrations may be used if the dye developer is utilized as a component of the liquid processing composition. In an especially useful mode of disposing the dye developers in the photosensitive elements, the dye developer is dis solved in a water-immiscible solvent and then dispersed in a gelatin coating solution. The coating solution is then applied to the photosensitive element, which pared, in the sequence desired.

The liquid processing composition which is used in the processes herein disclosed comprises at least an aqueous is to be pre' solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate and may contain the dye developer. In some instances, it may contain a conventional developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting film-forming material of the type which, when spread over a water-absorbent base, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials whose ability to increase viscosity is substanstantially unaffected when in solution for a long period of time may also be used.

The novel dye developers of this invention are aminoanthraquinone dyes which have a developing moiety or moieties joined to an amino substituent substituted directly on the anthraquinone nucleus through a bivalent organic radical comprising at least one methylene group. These dye developers may be defined as anthraquinone dyes, in which at least one and not more than two of the nuclear carbon atoms of the anthraquinone nucleus of said dye have linked directly thereto a radical of the formula:

wherein Z is a bivalent organic radical containing at least one methylene (-CH group, preferably a lower alkylene group such as methylene, ethylene, isopropylene, etc.; and X is a benzenoid silver halide developing radical and is preferably a dihydroxyphenyl silver halide developing radical such as p-dihydroxyphenyl, o-dihydroxyphenyl, and suitably substituted derivatives thereof.

The anthraquinone nucleus may and in general will contain other substituents which impart specific desired chemical and/or physical characteristics to the dye, e.g., substituents which contribute to the spectral absorption characteristics of the compound. Such other substituents are well known in the dye art and per se comprise no part of the present invention.

One class of dye developers within the scope of Formula 1 may be represented by the following formula:

wherein A is an anthraquinone nucleus; each Y may be a hydrogen, amino, alkyl, phenyl, halogen, alkylamino, phenylamino, phenoxy, alkoxy, hydroxyl, alkylsulfonamido, phenylsulfonamido; carboxamido, carbamyl, nitro, or cyano radical; m is a positive integer less than 5 and preferably less than 3; and Z and X have the meanings heretofore given in Formula 1.

It should be understood that when the Y substituent includes a phenyl or alkyl group, such phenyl and alkyl group may be further substituted by other substituents commonly found on such groups, e.g., hydroxy, amino, halogen, etc. groups.

The dye developers of this invention, as illustrated by Formulae 1 and 1a, are further characterized in that the only developing moiety present in the dye developer molecule is that present in the NHZX substituent. In this respect, the novel dye developers of this invention are distinguished from those dye developers disclosed and claimed in US. Patent No. 2,983,605, issued on May 9, 1961, to Richard S. Corley. It is to be noted, however, that as is stated in the abovementioned patent, the dye developers of this invention are also useful as intermediates in the preparation of the acylated dye developers of said patent.

In a preferred embodiment of the present invention the -NH-Z-X moieties are substituted in the a-positions of the anthraquinone nucleus.

One class of dye developers within the scope of the invention as illustrated by Formulae l and 1a and which 4 have been found to be particularly useful are those wherein m is 2 and the NHZX radicals are substituted in the 1 and 4 positions.

Such developers may be represented by the formula:

Although the length of such alkyl groups may be varied, especially useful results have been obtained when said alkyl group comprises less than six carbon atoms. The dye developers within this class may be represented by the formula:

O NH-R wherein Y, Z, -X are the same as above and R is an alkyl, preferably a hydroxylalkyl and more preferably a liydroxy-sec-alkyl group.

Still another class of developers within the scope of this invention which have been found particularly useful are the compounds corresponding to the compounds within Formulae 2 and 3 wherein Y in the 5 and 8 positions is a hydroxy group.

The expression bivalent organic radical, as used herein refers to organic radicals having two valences available for joining two atoms or radicals. As examples of bivalent organic radicals comprehended by the radical Z, mention may be made of alkylene radicals such as (1H3 CH -CH -CHCH- as well as alkarylene bivalent radicals such as It is also intended that Z may be saturated, unsaturated, such as CH CH=CHCH or substituted, such as chloroalkylene or hydroxyalkylene. Experience has indicated that where Z is an alkylene group, best results are obtained by the use of a lower alkylene group, e.g., an alkylene group containing less than about six carbons, and preferably an isopropylene (CHCIIz) group. It should be understood that Z may be an alkylene group comprising six or more carbon atoms provided that the resulting dye developer is capable of being dissolved in the liquid processing composition described herein, and its oxidation product rendered immobile.

The copending application of Elkan R. Blout and Myron S. Simon, Serial No. 449,514, filed August 12, 1954 (now abandoned), discloses and claims certain novel dye developers containing an anthraquinone ring similar to those set forth above. The dye developers herein disclosed and claimed may be distinguished therefrom in that the dye developers of the present application contain the bivalent organic radical Z, and such dye developers have been found to be photographically superior to those set forth in the above-mentioned application, especially as regards their brightness and purity of color. Moreover, particu- [larly when Z is a lower alkylene group, there is a substantial unexpected increase in the density of the transfer images. The increase in density is especially marked when Z is a secondary alkylene group, e.g., an isopropylone group and more particularly when the secondary carbon atom of such secondary alkylene groups is adjacent the amino group. It is believed that this superiority is attributable to the ability of the bivalent organic radical to insulate the silver halide developer radical from the amino-substituted anthraquinone.

The novel dye developers of this invention may be prepared by the replacement of sulf-o, halogen, nitro, hydroxyl, alkoxy or amino substituents on anthraquinone nuclei by amino groups derived from amines having the formula:

wherein Z and X have the same meaning as set forth above.

The 1 and 4 substituted anthraquinones such as those represented by Formulae 2 and 3 may be conveniently prepared from 1,4-diaminoanthraquinones and from 1,4- dihydroxyanthraquinones, i.e., quinizarins. When quinizarin is used in the preparation of the compounds, herein disclosed, the quinizarin may be first reduced to leuco quinizarin, then condensed, and the resulting product oxidized to the anthraquinone, by for example, aerial oxidation. When it is desired to prepare the dye developers herein disclosed directly from quinizarin it has been found that the reaction may be facilitated by carrying it out in the presence of an acid-acceptor and a monohydroxy-substituted aryl compound. As examples of monohydroxysubstituted aryl compounds, mentionmay be made of phenol, naphthol, cresol, xylol, etc. It has been further found that the condensation of quinizarin with the amine may also be facilitated by carrying the reaction out in the presence of an acid-acceptor and an orthoor paradihydroxy-substituted aryl compound. As examples orthoand paradihydroxy-substituted aryl compounds, mention may be made of hydroquinone, catechol, naphthohydroquinone, and l,Z-dihydroxynaphthalene.

The dye developers within Formula 3 may be prepared by condensing an anthraquinone such as quinizarin with about an equivalent of an amine within Formula 4 and then with about anequivalent of an amine within formula:

wherein R is the same as above. It will be understood that the order of condensing the amines may be reversed to suit particular needs. It will be further understood that dye developers within Formula 2 wherein the radicals are different may be similarly prepared.

The compounds within the scope of this invention may be further prepared by condensing an amino-substituted anthraquinone with a haloalkyl-substituted benzenoid silver halide developer.

It should be noted that the process of this invention permits one to convert compounds which are not dyes into products which are both dyes and photographic develop ing agents.

In certain instances, in using the dye developers herein disclosed in photographic processes, it may be desirable to temporarily shift the light absorption characteristics of such dye developers so that they absorb less light of the higher wave lengths. One such instance when such a shift is desirable occurs when a cyan dye developer, such as the 1,4-diamino-substituted developers disclosed herein, are disposed in red-sensitive silver halide emulsions. In such a use it may be desirable that said dye developers absorb less red light until at least after exposure. In instances such as this and in other instances where such a shift is desirable, it has been found that the leuco-form 0f the anthraquinones may be employed. When it is desired to shift the color back, such as, for example, after exposure or transfer, such a shift maybe made by a simple oxidation, e.g., aerial oxidation.

X has been defined as a benzenoid silver halide developing radical. Such benzenoid silver halide developers in general comprise an aryl nucleus which is substituted by at least two substituents selected from the group consisting of amino, alkylamino and/or hydroxyl groups. The amino, alkylamino, and hydroxyl substituents are usually substituted in .orthoor pararelationship with respect to each other, however, in polynuclear benzenoid developers they may be substituted in different rings. When substituted in different rings the positions which such substituents must occupy with respect to each other in order to provide a developing function are known from texts, such as, for example, The Theory of the Photographic Process, C. E. K. Mees, (revised edition, 1954), The Macmillan Co., New York, N.Y., p. 544 et seq. In a preferred embodiment of this invention the benzenoid silver halide developing radical isselected from those comprising dihydroxy-substituted benzene or naphthalene nuclei and more preferably comprises an orthoor ,paradihydroxybenzene radical. The para-dihydroxyben zenes have been found particularly useful. It should be noted that the radical X may contain substituents other than those which supply the silver halide developing function so long as such substituents do not adversely affect the silver halide developing ability; such substituents include alkyl, alkoxy, hydroxy, amino, halogen, etc.

Where the developing function possessed by X is supplied by hydroxyl or amino groups, it may be desirable to protect these groups, during synthesis, as by acylation, to avoid side reactions or oxidation. The protective groups are removed, as by hydrolysis, prior to photographic use.

As eXamples of dye developers within the scope of this invention, mention may be made .of

OH CH3 lA-bisa-methyl-B-llydroquinonyl-ethylamino) -anthraquinone OH 01 13 011i NH-e H CH2 Nn-on-onr OHO 1,4-bisa-methyl-Bhydr0quinonyl-ethylamino) -5,8- dihydroxyanthraqui'none 1- a-hydroxymethyl-propylamino -4 a-methyl-B-hydroquinonyl-e thylamino) -anthraquinone 1- a-hydroxymethyl-propylamino) -4- ametl1yl-fi-hydr0- quinonyl-ethylamino) -5,8-dillydroxyanthraqu'inone Other dye developers which have been prepared and are illustrative of the compounds within the scope of this invention include:

1-hydroxy-4- a-methyl-hydroquinonylethylamino) anthraquinone.

1,4-bis- 'y-hydroquinonyl-a-rnethyl-propylamino) -5,8-

dihydroxyanthraquinone.

1,4-bisa-methyl-y-hydroquinonylpropylarnino anthraquin one.

l,S-bis-hydroquinonylmethylamino-anthraquinone.

1,4-bis-hydroquinonylmethylamino-anthraquinone.

1,4-bisa-methyl-fi-hydroquinonylethylamino -6,7-

dichloroanthraquinone.

1- a-methyl-fl-hydroquinonylethylamino) -4- a-ethyl-B- hydroquinonylethylamino -anthraquinone.

1- a-methyl-B-hydro quinonylethylamino -4- a-ethyl-B- hydroquinonylethylamino ,S-dihydroxyanthraquinone.

1,4-bis- (a-methyl-2',5 '-dihydroxybenzylamino anthraquin one.

1,4-bisa-methyl-B-hydroquinonylethylamino -5 ,S-bisbenzene-sulfonamido-anthraquinone.

1,4-bisa-methyl-B-hydroquinonylethylamino -5- hydroxy-8-amino-anthraquinone.

1- a-hydroxymethyl-propylamino) -4- a-methylfl-hydroquinonylethylamino -5-hydroxyanthraquinone.

1,4-bisa-methyl-fi-hydroquinonylethylamino) -5- hydroxyanthraquinone.

1,4-bis- B-hydroquinonyl-ethylamino -anthraquinone.

1- [p- (fi-hydroquinonyl-ethyl -phenylamino] anthra quinone.

1- a-hydroxymethyl-propylamino -4- [3- (4-methyl-2',5

dihydroxyphenyl -a-methyl-ethylamino] -anthraquinone.

1-ethylan1ino-4- fi- 3 ',4-dihydroxyphenyl -ethylamino] anthraquinone.

1-chloro-4- fl-hydroquinonylethylamino anthraquinone.

1-hydroxy-4- [3- 3,4-dihydroxyphenyl) -ethylamino] anthraquinone.

1-chloro-5-(B-hydroquinonyl-ethylamino -anthraquinone.

1,4-bis- B- (3,4-dihydroxyphenyl) -ethylamino] -5 ,8-

dihydroxyanthraquinone.

1,8-bisfl- 3 '4-dihydroxyphenyl-ethylamino] anthraquinone.

1- [B- (3 ,4'-dihydroxyphenyl -ethylamino] anthraquinone.

1-fl-hydroquinonyl-ethylamino-anthraquinone.

1,5 -bis- [3- 3,4-dihydroxyphenyl) -ethylamino] anthraquinone.

1,5-bis- (fl-hydroquinonyl-ethylamino) -anthraquinone.

1,8-bisfl-hydroquinonyl-ethylamino -anthraquinone.

1- B- 3 ',4-dihydroxyphenyl) -ethylamino1-5-nitroanthraquinone.

1,5-bis- (a-methyl-B-hydro quinonyl-ethylamino) anthraquinone.

1 (,B-hydroxyethylamino) -4- (fl-hydroquinonyl-ethylamino) -anthraquinone.

1,4-bis- B- 3 ,4'-dihydroxyphenyl -ethyl amino] anthraquinone.

1- B-hydroxyethylamino -4- a-methyl-[i-hydroquinonylethylamino -S,8-dihydroxyanthraquinone.

1,4-bisa-ethyl-fi-hydroquinonyl-ethylamino anthraquinone.

1-methylamino-4- fl-hydro quinonyl-ethylamino anthraquinone.

l-fi-hydroxyethylamino-4- a-methyl-B-hydroquinonylethylamino) -anthraquinone.

1-amino-4- a-methyl-fl-hydroquinonyl-ethylamino anthraquinone.

1,4-bisa-methyl-fl-hydroquinonyl-ethylamino -5 ,8-

dimethylanthraquinone.

1-phenylamino-4-( a-methyl-,B-hydroquinonyl-ethylamino) -anthraquinone.

1,4-bis- (a-methyl-p-hyd'roquinonyl-ethylamino -2- methyl-5 ,8-bis-methoxyanthraquinone.

1,4-bisa-methyl-fi-hydroquinonyl-ethylamino -5- hydroxy-8-amino-anthraquinone.

As examples of additional compounds within the scope of this invention, mention may be made of:

1,4-bis- (oa-methyl-B-hydroquinonyl-ethylamino -6-phenylanthraquinone.

1,4-bisa-methyl-p-hydroquinonyl-ethylamino) -5,8-bismethyl-sulfonarnido-anthraquinone.

1-amino-2-cyano-4- a-methyl-B-hydro quinonyl-ethylamino) -anthraquinone.

1-amino-2-carbamyl-4- a-methyl-fi-hydro quinonyl-ethylamino)-anthraquinone.

1-phenoxy-4- B-hydroquinonyl-ethyl-amino anthraquinone.

1,4-bis- (,B-hydroquinonyl-ethylamino -5 ,8-acetamidoanthraquinone.

When the developing group in the compounds of the present invention is an ortho-dihydroxyphenyl group, the alkylene linking group (represented by Z in the above formula) is preferably connected to a nuclear carbon atom which is meta to one of the hydroxy groups, e.g.,

The following nonlimiting examples illustrate the preparation of dye developers within the scope of this invention:

Example 1 One mole of leucoquinizarin and four moles of 4-(betaaminoethyl)-catechol hydrohromide are refluxed in butanol for four hours under nitrogen in the presence of four moles of sodium bicarbonate. The reaction mixture is then acidified with dilute hydrochloric acid (in the presence of sufficient methanol to maintain a single liquid phase) and filtered. The precipitate is oxidized by dissolving in pyridine open to the air and boiling until no further color change takes place. Crystallization from ethyl acetate-petroleum ether yields 1,4-bis-[beta-(3.4'-

dihydroxyphenyl)-ethylamino]-anthraquinone, melting at 159-161 C. This compound is soluble in acetone, ethyl alcohol, ethyl acetate and pyridine, and insoluble in water and petroleum ether. It is stable in neurtal or acid solution, but unstable in base in the presence of air. Analysis of the product shows:

Calculated: C, 70.6; H, 5.1; N, 5.5. Found: C, 70.5; H, 5.3; N, 5.1.

Example 2 Leucoquinizarin (1.2 g.; 0.005 mole), Z-beta-aminoethyl)-hydroquinone hydrobromide (2.8 g.; 0.012 mole), and sodium bicarbonate (0.01 g.; 0.012 mole) are refluxed in 25 ml. of pyridine for two hours under nitrogen. One ml. of concentrated hydrochloric acid and one ml. of water are added to the reaction mixture and air is bubbled through at the reflux point until the color of the reaction mixture has gone to a clear blue without traces of green color. The reaction mixture is filtered into 150 ml. of 10% hydrochloric acid, the filtrate cooled in ice, and filtered. The solid is washed with water and ethyl acetate and then dissolved in ethanol and concentrated (under nitrogen) to give 0.5 g. (32% yield) of 1,4-bis-(betahydroquinonyl-ethylamino)anthraquinone melting at 154-157 C. Concentration of the mother liquor gives an additional yield of 1.03 g. of product of lesser purity. The product in an ethanol solution is pure blue in color in daylight. It is slightly soluble in acetone and ethyl acetate, soluble in alcohol and pyridine but insoluble in Water and petroleum ether. It is stable in neutral or acid solution, but unstable in base in the presence of air. Nitrogen analysis of the product shows a nitrogen value of 5.8% as compared with a calculated value of 5.5%.

It has been found that the yield of the desired 1,4- bis [beta (2',5'-dihydroxyphenyl)-ethylarnino]-anthraquinone may be increased, and its purification simplified, by increasing the reaction time, as illustrated by the following example:

Example 3 Leucoquinizarin (2.3 g.; 0.0097 mole), Z-(beta-aminoethyl)-hydroquinone hydrobromide (5 g.; 0.021 mole), and sodium bicarbonate (1.8 g.; 0.021 mole) are refluxed, under nitrogen, for 21 hours in 100 cc. of pyridine and 3 cc. of water. The reaction mixture is then cooled below the boiling point. A 1:1 concentrated hydrochloric acid and water mixture (4 cc.) is added. Air is bubbled through the mixture at the reflux point until the color of the mixture has gone to a clear blue without traces of a green color. The solution is cooled and then filtered into excess hydrochloric acid. The resulting precipitate is filtered, washed with water, and pulverized. The pulverized product is washed with hot alcohol to obtain 3 g. (60.3% yield) of the desired 1,4-bis-[betahydroquinonyl-ethylamino]-anthraquinone. The ethanol washings are precipitated with water and the precipitate washed with hot ethanol to obtain an additonal 0.3 g. of the desired product.

Although hydrobromide salts of the compounds have been used in the above examples, the

free amine or other salts thereof, e.g., the hydrochloride, may be used.

Example 4 10 product was precipitated into dilute hydrochloric acid and purified twice from acetone into water. The resulting precipitate was further washed with a 5 to 10% acetone-water solution until the washings no longer showed a yellow-brown color. The product was heated with 300 cc. of ethyl acetate until most of it dissolved. The undissolved material was l-(fi-hydroquinonyl-amethyl-ethylamino)-4-hydroxy-anthraquinone. The ethyl acetate solution was concentrated under nitrogen to about cc. and precipitated into hexane. The ethyl acetatehexane purification was repeated and then followed with a crystallization from a (4 to 6 by volume) water-ethyleneglycol monomethyl ether solution. The 1,4-bis-(;3- hydroquinonyl-ec-methyl-ethylamino)-anthraquinone produced sinters at 130 to 132 C. and a spectrographic analysis showed the following:

The following Example 5 provides an alternative method for preparing the compound of Example 4 using quinizarin.

Example 5 2.4 g. quinizarin (0.01 mole), 8.6 g. fi-amino-u-methylethylhydroquinone-hydrobromide (0.035 mole), 0.34 g. sodium carbonate, 3.4 phenol (0.036 mole), 12 cc. ethanol and 8 cc. of water were mixed together and deaerated with nitrogen. The mixture was then refluxed under nitrogen for 72 hours, then cooled and washed out of the reaction flask with a dilute hydrochloric acid solution into ice water. The resulting precipitate was filtered, washed several times with warm water and dissolved in acetone. The acetone solution was filtered and poured with rapid stirring into a large volume of an iced 2% hydrochloric acid solution. The resulting precipitate was warmed on a steam bath .to 40 C. to aid coagulation, filtered while still warm and washed with water. The product was purified twice from acetone into hexane and dried under a heat lamp.

Example 6 5.5 g. of 5,8-bis-benzenesulfonamide-quinizarin (0.01 mole), 9.95 g. of B-amino-mmethyl-ethylhyd'roquinonehydrobromide (0.04 mole), 1.8 g. of sodium carbonate, 3.4 g. of sodium bicarbonate and 3.75 g. phenol were placed in a deaerated flask, mixed with a nitrogen deaerated solution comprising 17 ml. of 95% ethanol and 11.5 ml. of water and reacted under nitrogen at a temperature of 7 C. for 101 hours. The reaction mixture was precipitated into a 2% hydrochloric acid solution filtered, and the resulting precipitate was redispersed in a 2% hydrochloric acid solution. The precipitate was then filtered and washed with a 2% hydrochloric acid solution until the washings were colorless. The product was then precipitated from ethyleneglycol monomethyl ether into dilute hydrochloric acid, filtered and dried. The product was further purified by twice precipitating it from ethyl acetate into hexane. The 5,8 bis-benzenesulfonamido-1,4-bis-(fl-hydroquinonyl-amethyl-ethylamino)-anthraquinone produced sintered at 142 C., and, upon a spectrographic analysis in ethyleneglycol monomethyl .ether, showed the following:

Example 7 2.3 g. of leuco-1,4,5,8-tetrahydroxyanthraquinone, 5.6 g. of 2-aminopropyl hydroquinone 'hydrobromide and 1.9 g. sodium bicarbonate were dissolved in 50 ml. of

pyridine and 2 ml. of water and refluxed for 64 hours.

The solution was aerated .at

its boiling point for 1.2 hours and then allowed ,to stand at room temperature for an The .product was precipitated into a 10% hydrochloric acid solution and taken up in 300 ml. of methanol. The methanol solution was evaporated until crystallization began and then it was allowed to stand overnight. The 1,4-bis-(fl-hydroquinonyl-ot-methyl-ethylamino)-5,8-dihydroxyanthraquinone produced had a melting point of 224 C. and upon a spectrographic analysis showed the following:

Example 8 36.0 g. quinizarin (0.15 mole) and 50 g. phenol were added to 180 ml. of ethanol and 120 ml. of water and deaerated with nitrogen. g. of sodium carbonate and 13.4 g. of 2-amino-1-butanol (0.15 mole) were added and the mixture was refluxed for 40 minutes under nitrogen. 37.2 g. of 2-aminopropylhydroquinone-hydrobromide (0.15 mole) and 12.6 g. sodium bicarbonate were then added and refluxing was continued under nitrogen for another 22 hours until the reaction was completed. The reaction mixture was poured into hydrochloric acid yielding a gummy mass. The gummy mass was purified twice from acetone into dilute hydrochloric acid and then from ethyleneglycol monomethyl ether into dilute hydrochloric acid. The mass was further purified twice from ethylacetate into hexane and dried in a vacuum desiccator. The 1-(a-hydroxymethylpropy]amino)-4-({3- hydroquinonyl-a-methyl-ethylamino) anthraquinone obtained showed the following in a spectrograph analysis:

Example 9 13.7 g. of leuco-1,4,5,8 -tetrahydroxyanthraquinone (0.05 mole), 12.4 g. of Z-aminopropylhydroquinone-hydrobromide (0.05 mole) and 4.2 g. of sodium bicarbonate (0.05 mole) were added to 150 ml. of pyridine and refluxed for 24 hours under nitrogen. 5.0 g. of 2- aminobutanol (0.056 mole) were added and the refluxing was continued another 24 hours under nitrogen. 5 cc. of concentrated hydrochloric acid were added and air was bubbled through the solution at 70-85 C. for about 24 hours. The mixture was cooled and added to a solution comprising 3000 ml. of water and 250 ml. of concentrated hydrochloric acid. The resulting precipitate was filtered off and washed with cold water until the filtrate was colorless. The solid was vacuum dried, powdered and mixed with 1 to 2 volumes of celite and extracted with 200-300 ml. of ethyl acetate in a Soxhlet extractor until the extract was nearly colorless. Upon cooling, the extract was stirred into about 2500 ml. of hexane and the resulting precipitate was filtered and dried. The l-(ahydroxymethyl propylamino) 4 ([3 hydroquinonyl-amethyl ethylamino) 5,8 dihydroxyanthraquinone produced, showed, upon a spectrographic analysis, the following:

Example 10 2.56 g. of 1,4,5-trihydroxy-anthraquinone (0.01 mole), 8.6 g. of 2 aminopropylhydroquinone hydrobromide (0.036 mole), 0.34 g. of sodium carbonate, 2.9 g. sodium bicarbonate (0.36 mole) and 3.4 g. of phenol were added to ml. of water and ml. of ethanol and refluxed under nitrogen for 49 hours. The reaction mixture was poured into a 15% hydrochloric acid solution and the resulting precipitate was filtered and washed several times with water. To insure the absence of leuco material the precipitate was dissolved in boiling pyridine in air, then precipitated into dilute hydrochloric acid. The resulting gummy solid was precipitated from acetone into hexane and dissolved in methyl acetate. The methyl acetate solution was concentrated and, on cooling, the product crystallized out in microneedles. The product was filtered, washed several times with methyl acetate containing enough hexane to prevent solubilization, and dried at room temperature overnight. The 5-hydroxy-1,4-bis-(B- hydroquinonyl-ot-methyl-ethylamino)-anthraquinone produced melted at 1506 C. and showed the following in a spectrographic analysis using ethyleneglycol monomethyl ether as the solvent:

Example 11 The procedure of Example 6 was followed except that 3.09 g. of 6,7-dichloroquinizarin (0.01 mole) was used in place of the 5,8-benzene-sulfonamidoquinizarin. After reacting at reflux for hours the reaction mixture was cooled and added to 160 ml. of 10% hydrochloric acid to precipitate the product. The product was purified once from acetone into dilute hydrochloric acid and a second time from warm acetone into hexane. The 1,4-bis-(fihydroquinonyl-u-methyl-ethylamino -6,7-dichloro-anthraquinone produced, upon spectrographic analysis, showed the following:

An elemental nitrogen analysis showed the following:

Percent Calculated 4.63 Found 4.4

Example 12 1.4 g. of 1,8-dichloroanthraquinone, 5.9 g. B-aminoethylhydroquinone-hydrobrornide and 2.1 g. sodium bicarbonate were added to 15 cc. of quinoline and refluxed for 4 /2 hours under nitrogen. The reaction mixture was added to dilute hydrochloric acid and ice, filtered and washed with dilute hydrochloric. The precipitate was dissolved in ethyl alcohol under nitrogen, and the resulting ethyl alcohol solution was filtered and concentrated under nitrogen. The resulting crystalline product was filtered and washed with a small amount of cold ethanol. The product was still further purified by crystallization from ethanol under nitrogen. The resulting 1,8-bis-(l3- hydroquinonylethylamino)-anthraquinone sintered at 163 8 C. and upon a spectrographic analysis, using dimethyl formamide as the solvent, showed the following:

Example 13 1.2 g. of 1,S-dichloroanthraquinone, 6.0 g. B-aminoethylhydroquinone and 5.8 g. of sodium bicarbonate were added to cc. of quinoline and reacted at reflux for three hours. The quinoline was removed under vacuum and ethyl alcohol was added. Ethyl ether was then added and the resulting white precipitate was filtered. The filtrate was concentrated under vacuum and taken up in acetone from which it was precipitated into petroleum ether. The gummy product was precipitated twice from ethyl alcohol, once into dilute hydrochloric acid and once into water. The 1,5 bis (,B-hydroquinonylethylamino)- anthraquinone melts at to C. and upon a spectrographic analysis shows the following:

Example 14 1.99 g. of 1,5-dihydroxy-4,8-diaminoanthraquinone, 7.45 g. 5 hydroquinonyl a methyl-ethylamine-hydrobromide, 2.3 g. of sodium bicarbonate and 1 g. Zinc dust were placed in 15 ml. of butanol and refluxed under nitrogen for about 20 hours. The reaction mixture was filtered and poured into dilute hydrochloric acid. The resulting sludge was precipitated twice from ethyleneglycol monomethyl ether into saturated brine, dried very nitrogen for 22 hours.

The spectrum of the product obtained would indicate that it still was not completely purified.

Example 15 2.5 g. of l-nitro-anthraquinone and g. of fi-(paminophenyl) ethylhydroquinone 0,0 diacetatehydrochloride were dissolved in 50 ml. of ethyleneglycol monomethyl ether and refluxed for 24 hours. The reactive mixture was filtered and precipitated into 1.5% hydrochloric acid. The tarry product was purified twice from ethyleneglycol monomethyl ether into an aqueous sodium chloride-sodium acetate solution. The precipitate was taken up in ethanol and water, deaerated with nitrogen and hydrolized with dilute sodium hydroxide on a steam bath for about two minutes. The product 'was precipitated with hydrochloric acid and purified once again from ethyleneglycol monomethyl ether into an aqueous sodium chloride-sodium acetate solution. A spectrographic analysis of the 1 [p-(2',5'-dihydroxypheuethyl) phenylamino] anthraquinone showed the following:

e =6,400 at 503 m Example 16 V 12.0 g. of quinizarin, 13 g. of 2 aminoprop-ylhydroquinonehydzrobromide, 4.2 g. sodium bicarbonate, 1.7 g. of sodium carbonate and 17 g. of phenol were placed in 60 ml. of ethanol and 40 ml. of water and refluxed under Then 13.1 g. of 2 aminobutylhydroquinone-hydrobromide and 4.2 g. of sodium bicarbonate were added and the reaction mixture was refiuxed for another 24 hours under nitrogen. The reaction mixture was precipitated into dilute hydrochloric acid and twice purified from ethyleneglycol monomethyl ether into saturated brine. The product was thoroughly dried and precipitated twice from ethyl acetate into hexane. A spectrographic analysis of the 1 3 hydro quinonyl a methyl ethylamine)-4-(-y-hydroquinonyla-methyl-propylamino)-anthraquinone produced showed the following:

e =16,000 at 642 m Example 17 9.6 g. of quinizarin, 3.5 g. of Z-aminobutanol, 1.57 g. of sodium carbonate and 15.04 g. phenol were placed in 48 cc. of 95% ethanol and 32 cc. of water and re- 'flu'xed for 30 minutes.

10.48 g. of /8'- (4 methyl 2,5- dihyd'roxyphenyl) a methyl ethylamine hydrobromide and 3.36 g. of sodium bicarbonate were then added and refluxing was continued for 18 hours. The resulting product was precipitated into a 10% hydrochloric acid solution and washed first with dilute hydrochloric acid and then with water. The precipitate was taken up in dimethylformamide, precipitated into dilute hydrochloric acid, washed with hot water and dried in a vacuum desiccator to yield a product which melted at 131 to 152 C. The product was further purified by precipitation from ethyl acetate into hexane, filtration through activated alumina, using ethanol as an eluant,

and by precipitation once again from ethyl acetate into hexane. A spectrographic analysis of the l-(a-h-ydroxymethyl propylamino) 4 [B (4' methyl 2',5' dihydroxyphenyl) a methyl ethylamino] anthraquinone produced showed the following:

14 An example of a photographic use of the dye developers herein disclosed, and set forth by way of illustration only, is the following:

Example 18 A photosensitive element is prepared by coating a subcoated cellulose acetate film base with a 4% aqueous gelatin solution followed by coating with a solution comprising:

Cellulose acetate hydrogen phthalate g' 4 Acetone cc Methanol cc 20 1,4- bis-'[,8-(3',4'-di ydroxyphenyl)- ethylamino]-anthraquinone g 3.5

After this coating has dried, a silver iodobromide emulsion is applied. A liquid processing composition is prepared comprising:

Water cc Sodium carboxymethyl cellulose g 4.5 Sodium hydroxide g 1.5 Metol g 0.1

An image-receiving sheet is prepared by coating a polyvinylbutyral-coated baryta paper with a solution comprising:

N-methoxymethyl polyhexamethylene adipam-ide g 4 Isopropanol cc 80 Water a cc 20 The photosensitive element is exposed and the liquid processing composition is spread between the photosensitive element and the image-receiving element as these elements are brought into superposed relationship. After an imbibition period of one minute, the image-receiving element is separated and contains a cyan, positive dye image of the photographed subject.

Example 19 A photosensitive element is prepared by coating a subcoated cellulose acetate film base with a 4% aqueous gelatin solution followed by coating with a solution comprising:

The photosensitive element is exposed and the liquid processing composition spread between the photosensitive element and an image-receiving element, prepared as described in Example 18, as these elements are brought into superposed relationship. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a cyan positive dye image of the photographed subject.

Example 20 A photosensitive element is prepared as described in Example 18, using 2 g. of 1-chloro-4-(beta-hydroquinonylethylamino)-anthraquinone in lieu of the dye developer set forth in that example. A liquid processing composition-isprepared comprising:

Water cc 100 Sodium hydroxide g 2.0 Metol g 0.1 Ascorbic acid g 0.2 Sodium carboxymethyl cellulose g 4.5

The photosensitive element is exposed and'then brought into superposed relationship with an image-receiving element as the liquid processing composition is spread between said elements. The image-receiving element is prepared by applying a polyvinyl butyral coating to a cellulose acetate-coated baryta paper followed by a coating of a solution comprising:

N-methoxymethyl polyhexamethylene adipamide g 4 Ethanol cc 85 Furfuryl alcohol cc 15 After an imbibition period of approximately one minute, the image-receiving element is separated and contains a pink, positive dye image of the photographed subject.

Example 21 A photosensitive element was prepared by coating a gelatin-subcoated cellulose acetate film base with a 1 to 1 methanol-acetone solution comprising 3% of 1,4-bis- (a-methyl-fl-hydroquinonylethylamino) 5,8 dihydroxyanthraquinone and 4% of cellulose acetate hydrogen phthalate. After this coating was dried, a silver iodobromide emulsion was applied. The film was exposed and an aqueous processing solution:

Percent Sodium carboxymethyl cellulose 4.5 Potassium bromide 0.2 Sodium hydroxide 2.0 l-phenyl-B-pyrazolidone 0.2

was spread between the photosensitive element and a nylon, image-receiving element such as used in Example 18. After an imbibition period of one minute, the imagereceiving element was separated and contained a cyan image.

Example 22 A photosensitive element was prepared by coating a gelatin-subcoated film base with an acetone-methanol solution (4 to 1 by volume) comprising 3% of 1,4-bis-(amethyl fl hydroquinonylethylamino)-anthraquinone dye developer, as prepared in Example 4, and 4% of cellulose acetate hydrogen phthalate. A silver iodobromide emulsion was applied and the resulting element was exposed and processed in a manner similar to that employed in Example 21, except using 2.5% sodium hydroxide to produce a cyan transfer image.

Example 23 A gelatin-subcoated film support was coated first with a tetrahydrofuran solution comprising 3% of l-fi-hydroquinonylethylamino-anthraquinone and 4% of cellulose acetate hydrogen phthalate and then with an iodobromide emulsion. Upon exposing and processing, in a manner similar to that employed in Example 18, except using 4% sodium hydroxide, a salmon-pink image was obtained.

Example 24 A gelatin-subcoated film support was coated first with an acetone-methanol solution (4 to 1 by volume) comprising 3% of 1,5 bis (I3-hydroquinonylethylamino)- anthraquinone as prepared in Example 13, and 4% of cellulose acetate hydrogen phthalate and then with an iodobromide emulsion. Upon processing, using an imagereceiving element having a polyvinyl alcohol image-receiving layer and an aqueous solution comprising:

Percent Sodium carboxymethyl cellulose 4.5 Sodium hydroxide 2.0 Potassium bromide 0.2 Sodium carbonate 2.0 N-methyl-p-aminophenol sulfate 0.2

as the processing composition, a magenta image was obtained.

1 6 Example 25 A gelatin-subcoated film support was coated first with an acetone-methanol (4 to l by volume) solution comprising 3% of 1-[ 3-(3,4'-dihydroxyphenyl)-ethylamino]-5- nitroanthraquinone and 4% of cellulose acetate hydrogen phthalate and then with an iodobromide emulsion. Upon processing, in a manner similar to that employed in Example 21, a purple-magenta transfer image is obtained.

Example 27 A photosensitive element was prepared by coating a gelatin-subcoated film support first with a 1 to 1 acetonetetrahydrofuran coating solution comprising 4% of 1,5- bis-(a-methyl ,6 hydroquinonylethylamino)-anthraquinone and 4% of cellulose acetate hydrogen phthalate and then with a silver iodobromide emulsion. Upon processing, in a manner similar to that employed in Example 21, using a polyvinyl alcohol-receiving sheet, a magenta image was obtained.

Example 28 A gelatin-subcoated film support was first coated with an acetone-tetrahydrofuran coating solution (1 to 1 by volume) comprising 3% of 1-fl-hydroxyethylamino-4-flhydroquinonylethylamino-anthraquinone and 4% cellulose acetate hydrogen phthalate and then with a silver iodobromide emulsion. Upon exposing and processing, in a manner similar to that employed in Example 21, ex-

cept using an aqueous processing solution comprising:

Percent Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazolidone 0.2 Sodium hydroxide 2.5 Potassium bromide 0.2 Ascorbic acid 1.0

a cyan transfer image is obtained.

Example 29 A photosensitive element was prepared, as in Example 28, except that 3% of 1-methylamino-4-/3-hydroquinonylethylamino-anthraquinone was used in place of the l-B- hydroxyethylamino 4 p hydroquinonylethylaminoanthraquinone. Upon exposing and processing, in a manner similar to that in Example 21, a cyan image was obtained.

Example 30 An acetone-tetrahydrofuran coating solution (1 to l by volume) comprising 2% of cellulose acetate hydrogen phthalate and 5.5% of 1,4-bis-(a-methyl-fi-hydroquinonylethylamino) 5,S-bis-benzene-sulfonamido-anthraquinone, as prepared in Example 6, was coated on a gelatin-subcoated cellulose acetate support. When the coating had dried, a coating of an iodobromide emulsion was applied. The above photosensitive element was exposed and then processed by spreading an aqueous processing solution comprising:

Percent Sodium carboxymethyl cellulose 4.5 Sodium hydroxide 2.5 l-phenyl-3-pyrazolidone 1.0 2,S-bis-ethyleneiminohydroquinone 0.45 6-nitrobenzimidazole 0.26

Example 31 A photosensitive element, similar to that of Example 30, was prepared using 5.0% of 1-(a-hydroxymethyl-propylamino) 4 (a methyl-p-hydroquinonylethylamino)-anthraquinone, as prepared in Example 8, as the dye developer. Upon processing, in a manner similar to that used in Example 30, using a processing solution comprising:

Percent Sodium hydroxide 1.5 Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazo1idone 1.2 2,S-bis-ethyleneiminohydroquinone 0.925 6-nitrobenzimidazole 0.12

a cyan positive image of the photographed subject was'ob- 'tained.

Example 32 A photosensitive element, similar to that of Example 30, was prepared using 4% of 1,4-bis-(a-methyl-p-hydroquinonylethylamino)-5,8-dihydroxyanthraquinone, as prepared in Example 7, as the dye developer. Upon developing in a manner similar to that used in Example 30, using a processing solution comprising:

Percent Sodium hydroxide 1.5 Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazolidone 0.7 Tertiary-butyl hydroquinone 0.3 6-nitrobenzimidazole 0.126

a cyan positive image was obtained.

Example 33 A photosensitive element, similar to that of Example 30, was prepared using 5.5% of 1,4-bis-(a-methyl-B-hydroquinonylethylamino) 5 hydroxy-S-amino-anthroquinone as the dye developer. Upon processing, in a manner similar to that used in Example 30, using a processing solution comprising:

Percent Sodium hydroxide 2.0 Sodium carboxymethyl cellulose 4.5 l-phenyl-3-pyrazolidone 0.6 2,5-bis-ethyleneiminohydroquinone 0.4 6-nitrobenzimidazole 0.12

a cyan positive image was obtained.

Example 34 Example 35 A photosensitive element, similar to that of Example 34, was prepared using 5.5% of 1,4-bis-(a-methyl-B-hydroquinonylethylamino) -6,7-dichloroanthraquinone, 0.4% of 6-nitrobenzimidazole and 0.4% of Resoflex-R 296 in the coating solution. Upon developing, in a manner similar to that employed in Example 32, except reducing the 6-nitrobenzimidazole in the processing solution to 0.08%, a cyan positive image was obtained.

18 Example 36 A photosensitive element, similar to that of Example 30, was prepared using the l-(a-hydroxymethyl-propylamino 4-[13 (4' methyl-2',5-dihydroxyphenyl)-a-methyl-ethylamino]-anthraquinone as prepared in Example 17 as the developer. Upon developing in a manner similar to that employed in Example 30, a cyan positive image of the photographed subject was obtained.

The following example illustrates an embodiment of this invention wherein the leuco-form of the dye developer is used in a photosensitive element.

Example 37 A photosensitive element was made up similar to that in Example 21, using 3% of 1,4-bis-(p-hydroquinonylethylamino)-leuco-anthraquinone. Upon processing, in a manner similar to that employed in Example 21, and after allowing time for aerial oxidation, a cyan image was obtained.

The dye developers of this invention are also useful in integral multilayer photosensitive elements for use in multicolor diffusion transfer processes. As an example of such photosensitive elements, mention may be made of the photosensitive elements disclosed and claimed in the copending US. application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13, 1956, wherein at least two selectively sensitized photosensitive strata are superposed on a single support and are processed, simultaneously and without separation, with a single common image-receiving element. A suitable arrangement of this type comprises a support carrying a red-sensitive silver halide emulsion stratum, a green-sensitive silver holide emulsion stratum and a blue-sensitive silver halide emulsion stratum, said emulsions having associated therewith, respectively, a cyan dye developer, a magenta dye developer and a yellow dye developer. In one of the preferred embodiments of photosensitive elements of this type, the dye developers are disposed in separate alkalipermeable layers behind the photosensitive silver halide emulsion stratum with which they are associated.

The photosensitive elements within the scope of this invention may be used in roll film units which contain a plurality of photosensitive frames. The photosensitive elements of this invention are especially useful in composite roll film intended for use in a Polaroid Land Camera, sold by Polaroid Corporation, Cambridge 39, Massachusetts, or a similar camera structure such, for example, as the camera forming the subject matter of US. Patent No. 2,435,717, issued to Edwin H. Land on February 10, 1948. In general, such composite roll films comprise a photosensitive roll, a roll of image-receiving material and a plurality of pods containing an aqueous alkaline processing solution. The rolls and pods are so associated with each other that, upon processing, the photosensitive element may be superposed on the image-receiving element and the pods may be ruptured to spread the aqueous alkaline processing solution between the superposed elements. The nature and construction of the pods used in such units are well known to the art. See, for example, US. Patents Nos. 2,543,181 and 2,634,886, issued to Edwin H. Land.

It should be noted that certain dye developers within the scope of this invention may be subject to color changes as a result of pH changes in the portion of the image-receiving element to which they are diffused. Since the dye developer is generally rendered effective by solution in an aqueous alkaline liquid processing composition, it accordingly is necessary to assure that the environment in which the transferred and unreacted dye developer is deposited has, or is capable of attaining, the requisite pH value affording the desired color to the diffused dye developer. This may be accomplished by use of a volatile basic compound, such as diethylamine, in the liquid processing composition. If sodium hydroxide is utilized in the processing liquid, it becomes carbonated after processing and by contact with the air, and this is effective to provide the desired pH change. Further control of the pH of the transferred and unreacted dye developer may be had by utilizing an image-receiving element which is difficultly penetrable by alkali, for example an appropriate nylon such as N-methoxymethyl polyhexamethylene adipamide, or by the use of an image-receiving element in which an acid or an acid-forming compound, for example oleic acid, has been incorporated.

It will be noted that the liquid processing composition may, and in the above examples does, contain one or more conventional developers, such as Metol, ascorbic acid, hydroquinones, 3-pyrazolidones, e.g. 1-phenyl-3-pyrazolidone (Phenidone), and 1-phenyl-4,4-dimethyl-3-pyrazolidone. Although the dye developers in and of themselves can carry out the development, the conventional developers serve to accelerate an possibly initiate the action of the dye developer. In certain instances, it is believed that the oxidation of the dye developers may involve a cross oxidation with the oxidized conventional developers.

The dye developers of this invention may be used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers to obtain black and white, monochromatic or toned prints or negatives. By way of example, a developer composition suitable for such use may comprise an aqueous solution of approximately 12% of the dye developer, 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline wash- .ing medium or other medium in which the unreacted dye developer is soluble. The expression toned is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver.

It should be noted that the dye developers of this medium are self-sutficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction between a color former or coupler and the oxidiz/ed developing agent, as well as so-called auto-coupling processes in which color is obtained by a reaction of the oxidized developing agent with unoxidized developing agent.

It will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of imagereceiving elements and adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to impart the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in US. Patent No. 2,647,049 to Edwin H. Land.

As set forth above, the dye developers of this invention wherein Z is lower alkylene unexpectedly provide a substantial increase in the density of the transfer images as compared with images produced, under similar conditions, using the dye developers disclosed in the above-mentioned application Serial No. 449,514 now abandoned wherein the Z group is absent. The following chart is illustrative of this increase in density and gives a comparison under substantially similar test conditions between some of the dye developers of this invention and 1,4-bis-(2',5-dihydroxyanilino)-anthraquinone, one of the dye developers disclosed in application Serial No. 449,514 now abandoned wherein the Z group is absent.

The inventive concepts herein set forth are adaptable for the formation of colored images in accordance with the photographic products and processes described and claimed in the copending application of Edwin H. Land, Serial No. 448,441, filed August 9, 1954, now US. Patent No. 2,968,554, issued January 17, 1961.

The novel compounds herein disclosed are also suitable for use as dyes for textile fibres.

In the preceding portions of the specification the expression Color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black.

Since certain changes may be made in the above products, compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A compound selected from the group of compounds within the formula:

uan) wherein m is a positive integer less than 3, said (NH-ZX) radicals are substituted in alpha positions on said anthraquinone nucleus, each Y is selected from the group consisting of hydrogen, amino, alkyl, phenyl, halogen, alkylamino, hydroxyalkylamino, phenylamino, phenoxy, alkoxy, hydroxyl, alkylsulfonamido, phenylsulfonamido, carboxamido, carbamyl, nitro, and cyano groups, each Z is an alkylene group comprising less than six carbon atoms and each X is selected from the group consisting of orthoand para-dihydroxyphenyl radicals.

2. A compound as defined in claim 1 wherein m is 2 and the (-NH-Z-X) radicals are substituted in the 1 and 4 positions of said anthraquinone nucleus.

3. A compound as defined in claim 1 wherein Z is a secondary alkylene group and the secondary carbon atom of said alkylene group is attached to the amino radical.

4. A compound as defined in claim 1 wherein X is a 2,5-dihydroxyphenyl radical.

5. A compound as defined in claim 1 wherein X is a 2,5-dihydroxy-4'-methyl-phenyl group.

6. A compound as defined in claim 1 wherein X is an ortho-dihydroxyphenyl radical and the alkylene radical is joined to a carbon of the phenyl group which is meta to one of the hydroxy groups.

7. A compound as defined in claim 1 wherein m is one and the (-NHZX) radical is substituted in the 1 position of the anthraquinone nucleus and Y in the 4 position is an alkylamino group, the alkyl substituent of said alkylamino group comprising less than six carbon atoms.

3. A compound as defined in claim 1 wherein m is one and the (NH-ZX) radical is substituted in the 1 position of the anthraquinone nucleus and Y in the 4 position is a hydroxyalkylamino group comprising less than 6 carbon atoms.

9. A compound as defined in claim 1 wherein m is one and the (-NHZX) radical is substituted in the 1 position of the anthraquinone nucleus and Y in the 4 position is a hydroxy-secondary-alkylamino group comprising less than 6 carbon atoms and the secondary carbon atom of said alkyl group is attached to the amino radical.

10. 1,4 bis (a-methyl-fl-hydroquinonyl-ethylamino)- anthraquinone.

11. 1,4 bis (a-methyl-fi-hydroquinonyl-ethylamino)- 5,8-dihydroxy-anthraquinone.

12. 1 (a-hydroxymethyl-propylamino)-4-(a-methylp-hydroquinonyl-ethylamino)-anthraquinone.

13. 1 (a-hydroxymethyl-propylamino)-4-(oz-methyl- ;3 hydroquinonyl ethylamino) 5,8 dihydroxy-anthraquinone,

14. 1,4 bis-(a methyl-B-hydroquinonyl-ethylamino)- 5,8-bisbenzenesul-f0namido-anthraquinone.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS Great Britain. Germany.

LORRAINE A. WEINBERGER, Primary Examiner. LEON ZITVER, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 209 ,016 September 28 1965 Elkan R. Blout et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 35, for "inhibition" read imbibition column 7, in the first formula, for

CH OH CH OH 2 read 2 I| IHCHCH -CH lNH-CH-CH -CH line 73 for "3' 4 read 3 4 column 9 line 4 for "neurtal" read neutral line 72 for "rejuxed" read refluxed column 17, line 5, for "photgraphed" read photographed line 43, for "anthroquinone" read anthraquinone column 18, line 34, for "holide" read halide Signed and sealed this 24th day of September 1968.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A COMPOUND SELECTED FROM THE GROUP COMPOUNDS WITHIN THE FORMULA: 